The solution is very simple and easy to implement.
Reduce block reward to .1 - problem solved.
It would require a hard fork yes. However it's more important to know how we got here. Crypti (the coin Lisk has been forked from) had no inflation thus had no block reward. Nobody wanted to be a delegate, nobody cared. Without incentive only hardcore supporters will spend time and money on running nodes. I think the whole Crypti networks were running about 5-10 servers, ran by about 1-3 people.
So when Max and Oliver created Lisk they implemented the block rewards to solve this problem. However the block reward amount were calibrated for a much lower initial market cap. The result of the ICO were cleary many times over what they were expecting.
So this created a new problem, an extra strong financial motivation to be delegates, the consequences of something that you can see being played out right now.
I assume that they thought about changing the reward system, but the fact is that the inflation rate is something that was known by every investor before and during the ICO. People put money into the project being fully aware of it. As a matter of fact there were many posts about how the inflation is much lower than in some other coins, and I don't remember every being mentioned as a problem until recent days, when some people started harping on it, usually following it up with an agenda.
Changing something as fundamental as the inflation rate (even if to a downwards direction) for a coin with an ICO type distribution is kind of a questionable move.
So instead Max and the early community itself gone towards the idea of using parts of these forged funds for the betterment of Lisk, the funding of tools and apps for lisks, etc. A kind of trickle-down economy.
There are also alternate solutions, like increasing the active delegate numbers from 101 something that may very well happen down to road, but block propagation would significantly need to be improved first.
We will see how this will play out. We long time delegates won't easily let go of this concept or our own profits for that matter. If pool people want it, well... molon labe.